I don't think we'll be able to upload knowledge any time soon, as we're a long way from properly mapping how the brain handles this.

But visual inputs for VR/AR is much closer, as there is already some functional implants for something similar: having cameras produce neural stimuli has been a thing for a few decades now, and it's now at the stage where some blind people have been able to regain a limited form of vision despite not having functioning eyes. The tech is only going to get better, so at some point it can be used to augment normal vision.